


Two Ds are Better Than One

by Dragonsrose18



Series: Stories of Daddy Sans [2]
Category: Underfell - Fandom, Undertale (Video Game)
Genre: Anal Sex, Bara Sans (Undertale), Bara Underfell Sans - Freeform, Double Penetration, Dubious Consent, Dubious Consent (at first), Ecto-Penis (Undertale), F/M, Mating Cycles/In Heat, Multi, Plot What Plot/Porn Without Plot, Post-Undertale Pacifist Route, Reader Is Not Chara (Undertale), Reader Is Not Frisk (Undertale), Reader has a vagina, Shameless Smut, Smut, Threesome - F/M/M, Underfell Sans (Undertale), reader is female
Language: English
Status: Completed
Published: 2020-05-03
Updated: 2020-05-03
Packaged: 2021-03-01 17:00:22
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 1
Words: 4,107
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23980459
Author URL: https://archiveofourown.org/users/Dragonsrose18/pseuds/Dragonsrose18
Summary: You were worried about Sans. You went to check on him, but what happens next was NOT what you had expected.
Relationships: Sans (Undertale)/Reader, Sans (Undertale)/Reader/Other(s)
Series: Stories of Daddy Sans [2]
Series URL: https://archiveofourown.org/series/1660600
Comments: 9
Kudos: 153





	Two Ds are Better Than One

**Author's Note:**

> Request made by one M3rmaiden:
> 
> "Oh my god, I absolutely love the idea of Bara Sans. And just saying this is some grade A smut, fucking love it. If you are still open to requests I would love one about Underfell Sans and him just using this reader like a toy. Please keep up the great work! Can't wait to read more!"
> 
> You wish is my command, my dear!
> 
> I hope you enjoy it, hon.

You weren’t sure what to expect.

You and Sans have been friends for a while now, never leaving each other side and making terrible puns. Of course, most shy away from him because of his size, but you didn’t mind. He reminds you of a giant teddy bear. You never spend one day away from Sans, but days like these is when he disappears.

And it always worries you.

After Sans sent you text messages to stay away from his house for a while, you couldn’t help, but worry for your giant Skeleton friend. Especially when he ignores your texts and questions.

Even Papyrus himself isn’t answering your calls nor text as well.

It made you worried if not a bit suspicious.

Without thinking you made your way to Skeleton’s home; you didn’t know what to expect. 

You knocked a few times…. No answer.

You knocked again… still no answer.

So you turn the knob of the front door and slowly opened it, what greeted you was complete darkness…. And a smell that was… not bad nor good or sweet.

“H-hello? Sans?” You called out as you entered the dark house.

The only light source was the sun outside, and it was bright enough to notice how messy and dirty this house is. Papyrus was normally a clean freak that even a little stain makes him go into a frenzy. Where is he?

“Hello? Papyrus? Sans? Come on you guys you’re worrying me-“ You were cut off as the door slams loudly, causing you to shriek and jump. And now you were alone in the dark.

Or were you?

You didn’t know!

Your heart was pounding against your chest as you began to shake, “G-guys? Come on this isn’t funny anymore!” You were again greeted with silence.

Suddenly you felt a familiar spark on your skin as two big bony hands push you back into bare bulky ribs. You let out an “oof” on the impact as you heard a loud groan. That groan was way too deep to be your Sans. 

The smell from either was starting to fill your nose, it was so…. strong you had no idea what this is. Whatever this is…. It made your body feel… hot.

You looked up to see a glowing red eye flaring up as it looked down at you.

You felt so frozen like a deer caught in headlights. You didn’t know what to say or do. 

And that didn’t stop the Skeleton from moving his hands from your waist to your breasts. He growled ever so slightly as his hands gave your breast a light squeeze which finally made you move as you used all your strength to push his hands off you.

Sadly with all your force, he doesn’t budge…. He only growled more deeply as he gripped you tighter against his body. Suddenly something was poking your back…. You were so sure it wasn’t a rib. 

Your face suddenly felt hot, not noticing that the Skeleton’s hand moved once again from your arms and down your tank top as he felt your breast.

That is the last time I’m leaving home without a bra.

Your face was hotter than ever, you didn’t know what to do. You couldn’t move as the Skeleton pinched and pull your nipples causing you to moan. 

What was wrong was you?! You shouldn’t be ok with this! ….But you are?

Your body was becoming so warm that you didn’t notice that the Red-eyed Skeleton was nipping at your neck, that your jacket somehow slides off your body, and…. Another pair of hands ripped off your tank top like paper as you let out a startled scream.

And those same pair of hands were feeling your skin as he growled against your chest.

You looked down to see a glowing blue eye.

“S-sans?” You whispered out before a moan slipped past your lips as red-eyed Skeleton licked your neck with his long gooey tongue.

You took tried to take a good look at Sans, but since it was dark, and the only light was the two Skeleton’s glowing eyesocket which created a hue of dim purple light. But the one thing you notice for sure was how hot both are to you.

And their smell.

You couldn’t put your finger on it, but there was something about this smell.

Sans looked up at you as he started to attack the other side of your neck with nips and gooey kisses, “so…. so… good…. So…. ripe for… the taking.” He said through pants as he yanked your jeans and tore off your underwear, leaving you exposed and bare.

You screamed, but red-eyed Skeleton covered your mouth as he whispered, “relax.”

His voice was almost like Sans… except it was deeper almost smooth…. It was eerie. It almost makes the situation even scarier.

You would if the two Skeletons didn’t look like they were going to eat you alive.

Suddenly both Skeletons looked at each other than you as their grip tightens on you, but the other Skeleton’s grip was tight enough to bruise your skin; he probably has.

“gentle, red.” Sans growled, “Red” growled back louder and deeper. 

Like they were predators fighting over their prey.

And sadly, you were the frighten prey.

As Sans had his grip on your legs and Red with his grip on your torso, you felt a familiar nauseous that came and went. The two Skeletons shorted cut into what looks like Sans room….. Or what’s left of it.

Everything was almost…. Empty.

Along with Sans’ mattress, there is also his blankets and pillows bunched up together, it was almost like a nest.

A nest that was big enough to fit three people.

Without a thought or warning, you were thrown onto the nest and it wasn’t before long the two warm Skeletons were on you. Red was immediately on your breast, going back to pinching and…. Licking(?) your hardened nipples whilst Sans force your legs apart as he smelled your pussy.

You felt something tingling sliding up and down your thighs, you looked down to see Sans glowing hands. Staring intensely at your womanhood which caused you to blush like a shameless virgin. 

It wasn’t long before you felt that gooey tongue slowly trailing up your thigh, Sans then stopped before he reached your womanhood. 

He stared at your bare thigh for a moment, he was memorized by how soft your skin is.

Suddenly you felt the wetness of his tongue return, but it wasn’t long before Sans took his sharp fangs and bit down hard on your bare skin.

You were about to scream, but it was cut off when Red took the opportunity to stick his abnormally long tongue down your throat.

You could feel bits of blood dripping from your wound into Sans mouth, you would of cry in pain, but the noises coming from your throat were whimpers and low moans.

“S-should I be enjoying this?” You thought to yourself, but the thought immediately when you felt Sans’ thick phalanges rubbing your core.

He released you as he moved closer to your pussy and gave it a sniff.

Sans growled so pleasingly, “so…. wet.” 

Wet?! How the hell am I wet already?! 

He took his phalange to your pussy and slowly caress your clit, you bucked against his touch. 

It didn’t last long when he took two boney fingers and shoved them into your arching womanhood; you let out a moan, but it was cut off when Red released you from his gooey long tongue and grabbed you by the hair as he stepped over you. He shoved your face into his covered pelvis bone as he groaned and let out a cruel laugh, but what you felt wasn’t just bone.

It was so hot against your cheek, so hot and… and… So BIG through his shorts. 

He began to grind your face up and down, you could smell mustard and cigarettes as well as whatever that odor is.

After a while, you took out your tongue and started to lick the covered cock as Red grind harder against your face, as you lick you can taste the mustard with a bit of alcohol. You would have gagged at the taste, but Red pulled your hair as you watched him pull his shorts. 

His cock sprang free, his large cock was almost close to your face, you almost drooled at the sight. 

It was so big an-and red!

Without thinking you went to touch it, but it seems like that wasn’t what Red had in mind.

Without a warning, he gripped onto your hair and shoved his length into your mouth. He moved your head to go dipper and dipper onto his cock until its entire length was hitting the back of your throat. 

He kept his cock pushed against your throat as he threw his head back, groaning loudly. You choke around the harden length, tears coming out of your tightly shut eyes as you tried your hardest to breathe through your nose…. And most of all not to throw up your breakfast. 

Red gripped your hair tight and growled in a condescending voice that made your spine shiver, “look at me, whore.” You slowly and hesitatingly open one of your eyes, your vision blurred from your tears. Despite the darkness and your tear-blurred vision, you can see the drooling, hungry face of a Skeleton who was going to fuck your throat.

“that’s right….” He groans as he thrust his hips slowly, letting his cock hit the back of your throat. Each time he hits your throat, you let out an almost gagging whimper that soon became muffle moans.

After a while, you relaxed as Red begins to speed up his thrusting against your mouth, hitting your throat again and again as you massage the shaft with your tongue. The whole display of Red dominating your mouth had your body tingle, you didn’t know why you couldn’t help but drool and give in to the abuse Red was giving you.

The abuse that was making you… Oh so wet.

Suddenly you felt something hard and hot and throbbing rubbing against your wet pussy, you completely forgot Sans was there playing with your wet, dripping pussy.

You couldn’t see what he was doing since Red’s hand was permanently gripped on your hair, but you know what he was about to do!

You haven’t seen his dick but considering he’s about the same size as Red (Even if Red beat him by a few inches) his dick must be as massive as Red’s.

You were terrified, but at the same time drooled at the thought of him groping himself with the giant dick in his hand. 

Sadly, that thought ended when Sans place his cock at your entrance and started to push, which caused you to panic, No. NO! Wait! I-it’s too big! It won’t fit! IT WON’T FIT-

You arched your back as you screamed around Red’s dick as Sans shoved himself fully into you without any resistance. 

Amazingly, it didn’t hurt. 

It was the opposite, you felt so… full. 

His cock was huge inside of you…. It was almost like it was almost to your stomach.

Is that even possible?!

And with every little twitch from Sans’ cock, you shake and moan even louder around Red’s cock.

You heard Sans’ groan with delight and then chuckles darkly as he whispered, “so… tight…. so… perfect.” He didn’t waste any time as he slams his hips against yours, causing you to scream in pleasure.

His pace was rough and fast, it was almost punishing as he rams deep inside you. Rubbing and hitting spots you didn’t know to exist. 

Sans push your legs up as he pushes deeper inside, his ectoplasmic balls hitting your ass.

Though Sans’ intrusion felt wonderfully intoxicating, you jaw went slack as you woke up from your memorization as claws dig into your skin. Red forced his entire cock deep into your throat and hold you tightly as you felt his cum filled your mouth.

It was… too much.

Without thinking you swallowed all that you could.

His cum had a weird taste. Not that it was bad it kinda reminded you of the red Starburst candies you love so much. 

Though it had a bit of mint as well.

After a while, he let you go as he slides himself out of your mouth. You let out a gasping couch that turns into a pleasurable sigh as you let yourself relax as Sans thrust himself in and out of you. 

With your moans and his groans mixing like a lustful song, you didn’t hear a distant growl.

But you did feel pain from your scalp as giant skelly hands pulled you from Sans and flipped you on your stomach, letting out an undignified “oof” and leaving you empty and whimpering. 

You looked up and saw the glowing red hue of Red’s eyesocket was trained on you. You saw the look on his skeletal face and what you saw made you shiver in fear. He looked hungry, lustful, and yet somewhat angry as he gripped your hips to meet his as he fisted his cock and rubbed it against your wet, aching pussy. 

As you waited in anticipation you felt a familiar hold on your SOUL as you were lifted from the ground and back at the hands of Sans, only this time his grip tightens around your waist and lifted you against his arousal. 

Only this time, there wasn’t any teasing.

He moved his boney hands to spread your legs apart and roughly dropped you onto his throbbing cock. Penetrating your slick pussy; letting a long awaiting moan escape your lips as you arch your back against Sans covered sternum.

This felt so amazingly good, having Sans’ dick hit all the right places. Especially has he moved in such a brutal pace; he was moving so fast that you couldn’t feel the growl that roaring in his skelly throat. 

You looked up and saw he was glaring at Red with his blue hue eye, and you could have sworn you heard him growl “mine” as Red snarled like a wild animal.

But you didn’t care at the moment.

Not when his dick was pounding you even deeper than before. 

Not when he was hitting all the right nerves and spots that made you moan and squeal in delightful pleasure.

…Only to have that interrupted by a sudden rough grip of your SOUL again only this time this feeling was more cold and possessive touch not like the protective touch you are used to from Sans. 

This time you were turned around, your back to Red, as you were forced to slam against his sternum once again as he wrapped his hands around your legs, feeling his harden dick caressed against your ass. 

As he begins to push against your small hole, you felt yet another strong tug in your SOUL only this time you felt another presence in your SOUL. 

You looked up to see Sans bearing his fangs at Red as he growled and snarled at him with great intimation. They were both like wild animals fighting over pure instinct; fighting over their weak prey.

….And you, in the center, is the weak prey.

Suddenly your chest felt like it was about to break in two as the Skeletons were fighting over your body, it was getting harder to breathe, you were started to get lightheaded. You feel as if you were dying, maybe you will if you didn’t stop these two Alpha males tear you in half. 

You were awakened from your thoughts when you felt claws digging into your legs and thighs from the Skeletons monsters, only Sans drag his claws down your legs, the smell of iron filled your nose.

You open your mouth and spoke up, “Guys! Guys! S-stop please!” As soon as you spoke, they both did what you said and stop their movement as they eyed you with their glowing sockets, waiting patiently for you to continue. 

“W-well… U-umm I-I know you two are hurting…. Right now…. And Ummm…” You nervously gulped, “But there’s nothing wrong with sharing. After all, two dicks are better than one, right?” You felt your cheeks become warm as you nervously laughed a little while the two Skeleton stared blankly at you. 

After a moment of silence, Sans grip became loose and soft as he adjusts himself against your body, moving your legs to wrap around his unusual large body whilst you felt something wet and slimy against your ass as Red begins to push.

Sans took his hardening cock in his hand as he lined it against your still dripping cunt, he rubbed against you a couple of times before he pushed himself slowly.

Whilst Red was still slowly entering you, he lets out a small and pleasing groan as you let your head fall back onto his sternum, letting out an uncomfortable whine through your gritted teeth. Your juices from your pleasure help a bit, but Red was so…. goddamn BIG…. And you have never been stretch this like before.

But it wasn’t…. unpleasant.

Especially when Red finally has you taking his entire cock…. And there was no pain.

Just a dull ache and the feeling of Red’s dick twitching inside your ass making you feel… good.

It’s not that you are unfamiliar about anal, it’s just you never felt this way before. Even as Sans finally fully penetrates you, making your body go into a spaz from the pleasure.

Both Skeletons groan as soon as a moan left your left.

None of them attempted to move, making you whine from the lack of moment.

You looked up at Red than at Sans, you whimpered as you attempted to wiggle your hips around their glowing dick, only for Red to hold your hips while Sans grip your legs again. Whimpering in pain as the Skeletons smirked. 

“G-guys…Please…. Please move… I-I need you…. Both of you…” You whimpered.

Without a second thought, the Skeletons begin to move in sync. 

A loud cry escapes your lips as the Skeletons let out a series of groans, grunts, and growls turning the silence house into an orchestra of pants and lewd moans. All three of you were loud enough for the neighbors to hear, but at this moment you didn’t care.

You felt so…. good…. And full!

You never felt anything like this before.

The feeling of your pussy being stretched and Sans hitting all the rights spots as his claws dig into your legs again, blood was falling from Sans inhuman nails, but again you didn’t care. Red holding your waist for dear life as he rams his cock so deep into your as you could have sworn his dick was caressing your spine; like it was sending shockwaves through your body.

You loved it so much.

It felt so FUCKING GOOD!

It was like you were in heaven.

After a while, you felt your legs shake, the heat in your stomach begins to grow intensely as Sans begin to rub against your clit, fast and hard as Red removed one hand from your waist and begin to fondle your left breast’s nipple. Pinching and pulling it enough to make your cry-like moan.

You looked at Sans with pleading eyes, “Please please, please…. Sans…. M-make me cum….”

Shortly after your wish was granted.

Sans moved his thumb in a rough, fast pace while both he and Red pushed their limits and pounded you into complete ecstasy. Within a few seconds, you felt that heat inside of you explode as you arch your back into Red’s sternum. 

Through your blurred and post-orgasm haze, you heard the two Skeletons filled your ears with grunts and groans, and something warm and tingly filled your insides. You looked down to see your stomach extended, you were so full of Sans and Red cum. 

It was like you suddenly became pregnant. 

You also notice a purple-ish glow lighting through your stomach, you couldn’t help, but giggle.

You were like a human glow stick. 

You were pulled from your thoughts when Sans and Red slowly put you down onto their nest, you let out a weary sigh as you relaxed into the sheets.

Your whole body feels like Jell-O.

Your energy suddenly evaporated into nothingness.

You felt both of the Skeletons shift around you, but you didn’t care at the moment. You were about to shut your eyes and fall into a deep slumber…. Only to have awakened when you felt claws and the strong smell of Iron.

You flinched a little only to see the glow of Sans’ eyesocket.

Though the glow wasn’t as strong as it was before…. And he looked…. Distressed. 

“y-y/n?” Sans spoke shakingly. You realized this was the first time he talked normally all night… His boney brow was covered in Cyan sweat and you notice Cyan tears forming in his eye sockets, “i-i… y-you…” He looked down at your body, examining the damage he and Red did to you. 

He started to eye every bruise that is beginning to form and the bite marks he had left. The tears that threaten to form earlier began started to fall down his cheeks, “y/n….” He pulled you in a tight hug as he sobbed in your hair, “i-i’m s…..orr……y!” he stuttered through his sobbing, “i-i-I’m…m s…..soooorrrry!!!” 

You rubbed his back as you shush through his crying, “I-It’s ok, Sans. I’m not mad…. A little concern, but not mad.”

Sans hold you tighter, “y-you should…. y-you should…. b-be mad…. i-i’m so sorry, y/n!” 

You were about to speak again before a grunt and a deep, smooth voice interrupted, “’m not.”

Sans moved his head from your hair and bare his teeth, “shut the hell up, red.” 

You turn to see Red leaning against the wall relaxed and unfazed, you almost have forgotten about him. 

He doesn’t seem as bothered like Sans was.

“you don’t need to get yer panties in a twist, sansy,” Sans growled at that nickname, “we were both in heat, we couldn’t control our actions. plus your girlfriend looked like she enjoyed herself.” He then winked at you before adding, “if i had a kinky girl like her i wouldn’t even let her leave the bed.”

You looked at Sans, “Heat? Is that a monster thing?”

Sans cheeks glowed a misty blue before sighing, “thanks red.” He grumbled before he sat back down on the mattress.

“yeah, it’s a monster thing. whenever a monster is old enough, they go through a heat cycle, so it’s a seasonal thing. Meaning when a monster finds a mate, they…”

“they fuck and make monster babies.” Red interrupted, Sans, rolled his eyes at him, “thanks for summing it up for me, Red.” He said sarcastically as Red laughed like it was the funniest thing ever.

Though it didn’t stop you from a sudden panic you are experiencing. 

You touched your extended belly, you were about to speak up, but Sans beat you to it, “humans and monsters can’t have babies. Only if they have Soul-bonded at least.”

You let out a sigh of relief, “Good to know!”

“Anyway, how long are you two in heat?”

Sans and Red looked at each other before answering, “another week or so…. it can be longer sometimes.” Sans fidgets with his phalanges. “y-you can rest for a while here t-than you can g-go home…. if you want.”

Suddenly Red groans annoyingly, “stop being a baby, blue boy, she wants to stay. ain’t that right, sweetheart?”

Before you could answer Sans spoke up, “we’ve been fine before she showed! she can’t handle what we throw at her!”

“she handled what we did alright i don’t see why she can’t handle another few rounds with us.” Red chuckled as looks at you and licked his chomps.

You couldn’t help, but blush.

Sans was ready to commit bloody murder, but you quickly grabbed his hand and said, “I-I don’t mind helping…. As long as you guys want me. I-if it was anything like it was before I can handle two weeks.”

Sans looked down at you before he grabbed your hand, “y-you sure… you don’t have to do this.”

You then gave him your smuggest look you can master, “As I said, two D’s are better than one.”

Sans took a step back, surprised, whilst Red threw his head back and barked out a loud laugh, “oh-oh stars! i like this one.”

“you’re in for a bone-ified time, sweetheart.”

**Author's Note:**

> All comments and request are welcome.


End file.
